Tamper-evident container closures are not new per se. In the packaging of pharmaceutical products particularly over-the-counter products such as aspirin, and other drugs, it is important that the closure provide visual indicia of once having been opened in order to alert the user to possible tampering of the product in the container. Shrink wraps made of plastic have been employed to seal the juncture of the cap with the container when it is seated on the container. In order to remove the cap which may be a screw-type cap, the shrink wrap has to be physically torn which gives evidence to the user that the cap may have been once removed. It has been found that the process of assembling shrink wraps is relatively expensive. Furthermore, they are not truly tamper-proof in that if there is a loose fit, it presents the danger of the shrink wrapping being removed, tampering of the product and then reapplying the shrink wrap so that there is no visual indicia that the cap has been once opened.
Other types of tamper-proof closures are shown in the patents listed below.
______________________________________ Inventor Patent No. Issue Date Title of Invention ______________________________________ Fields 3,224,616 12-21-65 Closure and Method of Making Same Fields 3,329,295 07-04-67 Tamper-Indicating Closure Fields 3,438,528 04-15-69 Tamper-Indicating Closure Fields 3,504,818 04-07-70 Tamper Proof Bottle Closure Fields et al 3,455,478 07-15-69 Tamper-Indicating Closure Patel et al 4,147,268 04-03-79 Pilfer-Proof Closure For Containers de Wijn 4,205,755 06-03-80 Tamper-Proof Bottle Closure Ostrowsky 4,206,851 06-10-80 Tamperproof Closure ______________________________________
These closures generally comprise a screw cap made of plastic and having a tamper-evident band connected by fractuable bridges or scoring to the lower terminal edge of the skirt of the cap. The tamper band usually has a rib which coacts and engages under a flange on the container finish. Accordingly, when it is desired to remove the cap, the user simply turns it in the direction to unscrew the cap and the tamper-evident band is prevented from moving axially by reason of the inter-engaging ribs, bead and flange so that as tork is applied to the bridges connecting the tamper-evident band to the skirt fracture allowing the closure to separate from the band and be removed from the container. Thus, when the closure is removed from the container body, the separated band gives indication that the package has once been opened or possibly tampered with. While these closure assemblies are generally effected for the purposes intended, the present invention provides a tamper-evident closure assembly which is of relatively simplified construction, as easy and economical to manufacture and apply to a container and is truly tamper-proof.